title: In vivo antiprostate tumor potential of Vernonia guineensis Benth. (Asteraceae) tuber extract (VGDE) and the cytotoxicity of its major compound pentaisovaleryl sucrose.
abstract: BACKGROUND
  Vernonia guineensis Benth. (Asteraceae) root decoction is used in folk medicine in Cameroon to treat some ailments including prostate cancer. The aim of this study was to validate the claimed antiprostate cancer activity of Vernonia guineensis Benth. in vivo and to investigate the cytotoxicity of a pentaisovaleryl sucrose isolated from Vernonia guineensis on some cancer cell lines.
  
  
  METHODS
  A crude dichloromethane extract of Vernonia guineensis (VGDE) was used for this study. For in vivo antiprostate cancer efficacy, nude mice (n=16) were injected subcutaneously with prostate cancer PC-3 cells. Upon the formation of the xenograft tumors, the mice were divided into two equal groups with approximately the same mean tumor volume per group. One group was treated with VGDE orally (500 mg/kg) and the other with a vehicle control for 30 days. Body weight and tumor volumes were measured 2× a week and on the 33rd day, the mice were euthanized and tumors harvested and weighed. For the cytotoxicity study, the WST-1 assay was used to determine the activity of pentaisovaleryl sucrose previously isolated from VGDE. The cancer cell lines used in the cytotoxicity study included breast, colon, leukemia, lung, melanoma, ovarian and prostate.
  
  
  RESULTS
  Prostate cancer (PC-3) xenograft tumors treated with VGDE showed a significant decrease in tumor size (P=0.0295) compared to control. Pentaisovaleryl sucrose also demonstrated cytotoxicity against various cancer cell lines with IC₅₀ values as follows: MDA-MD-231-6.66µM; MCF-7-7.50 µM; HCT116-14.12 µM; A549-5.76 µM; HL60-6.43 µM; A375-8.64 µM; OVCAR3-9.53 µM; Capan1-7.13 µM; Mia-Paca 6.47 µM.
  
  
  CONCLUSIONS
  VGDE does possess in vivo activity against prostate tumor and has potential for development into a natural product for the treatment of prostate cancer. This study thus provides preliminary validation for the folk use of Vernonia guineensis against prostate conditions. Further in vivo studies are however required to confirm these results and to understand the mechanism of action of VGDE and the in vivo efficacy of pentaisovaleryl sucrose.
authors.affiliation: Virgin Botanicals & Biotech Inc., Columbia, MD, USA; Institute of Human Virology, University of Maryland School of Medicine, MD, USA. Electronic address: ntoyang@som.umaryland.edu.
authors.forename: Ngeh J
authors.initials: NJ
authors.lastname: Toyang
authors.forename: Eugene N
authors.initials: EN
authors.lastname: Ateh
authors.forename: Harry
authors.initials: H
authors.lastname: Davis
authors.forename: Pierre
authors.initials: P
authors.lastname: Tane
authors.forename: Luc B
authors.initials: LB
authors.lastname: Sondengam
authors.forename: Joseph
authors.initials: J
authors.lastname: Bryant
authors.forename: Rob
authors.initials: R
authors.lastname: Verpoorte
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D035281:Plant Tubers; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D013395:Sucrose / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use*; D035741:Vernonia; D023041:Xenograft Model Antitumor Assays
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D013395:Sucrose
keywords: Cytotoxicity; Pentaisovaleryl sucrose; Prostate cancer; Vernonia guineensis